Calling all Phenom II Overclocking Gurus!

[Enmity]

I have an unusual question for you. My situation is this, My phenom II 940 is overclocked to 3.8ghz by only raising the Vcore to 1.488 and multi to obtain this clock. I've found that my corsair ram (xms2 ddr2 800) will only clock a hair over 200fsb at 4-4-4-12. Ive also set the nb to 12x in bios - which sets the nb at 2400Mhz, however my bios has no way to set the nb voltage so 12x is the highest my bios will boot at.

I've tried dropping the timings down to 5-5-5-15 in the bios and then overclocking the fsb to roughly 250fsb...which raises the nb right up to 2800Mhz+, my ram would now be at 1000mhz and cpu clock at 3.8Ghz.

Both of these configurations yeild pretty much the same results.

What I'd like to know is is there a way to use a program to PERMINANTLY set the NB volts - even at boot, so then from the bios I could raise the nb multi higher - 13-14x therefore i wouldnt have to drop my ram timings from 4-4-4-12 since i know amd prefers low n tight as versus high n loose (with regard to ram, not women

Or - what would be the lowest cas 5 ram timings I could try coz i know that getting that nb up to 2.8Ghz+ performs really well - id just like to find a way to obtain this without compromising my ram timings.

I'll attach a screen of my current AOD settings for your reference.

any help or suggestions are much appreciated, cheers.

 

[Enmity]

added screenie

 

[Enmity]

Bump, anyone?

 

[kurosagi01]

the BEST and most SAFEST way to overclock a processor is by the BIOS,that way you can overclock the CPU and set the voltages, and it will remain at that voltage until you change it,if that helps.

 

[erocker]

Your bios most definitely has a NB voltage setting. Gigabyte wouldn't make a DQ6 board without one.

 

[TheShad0W]

What about the "NB VID" and "NB Core" voltage settings in the AMD overdrive utility (shown in your screenshot)...

 

[Enmity]

alright, so i managed to run a memory divider to force my ram to 667 rather than 800 and kept the timings of 4-4-4-12 then increased fsb until ram is back at 800mhz yeilding a nb speed of 2880mhz and cpu clock back at 3.8Ghz.

Now i just need to find out if it will perform better with the ram at 800mhz with 4-4-4-12, or whether it'll be faster at 1000Mhz @ 5-5-5-15

 

[Corduroy_Jr]

in bios press ctrl-f1 that should unlock more advanced overclocking options

 

[erocker]

alright, so i managed to run a memory divider to force my ram to 667 rather than 800 and kept the timings of 4-4-4-12 then increased fsb until ram is back at 800mhz yeilding a nb speed of 2880mhz and cpu clock back at 3.8Ghz.

Now i just need to find out if it will perform better with the ram at 800mhz with 4-4-4-12, or whether it'll be faster at 1000Mhz @ 5-5-5-15

Usually with AMD, a lower cas will yeild better results. 2880 on the NB is quite good for your CPU being at 3.8ghz. NB frequency directly improves the performance of the RAM.

 

[Corduroy_Jr]

alright, so i managed to run a memory divider to force my ram to 667 rather than 800 and kept the timings of 4-4-4-12 then increased fsb until ram is back at 800mhz yeilding a nb speed of 2880mhz and cpu clock back at 3.8Ghz.

Now i just need to find out if it will perform better with the ram at 800mhz with 4-4-4-12, or whether it'll be faster at 1000Mhz @ 5-5-5-15

4-4-4-12 or 1000Mhz @ 5-5-5-15 will give u same speeds, according that the rest of other timing are tight, your nb clock is way to high, higher nb clocks, will result in a lower overall cpu clock

hears some examples
cpu 3800mhz 1.5v nb 2400mhz 1.25v
cpu 3800mhz 1.6v, nb 2880 1.4v

its a balance thing, if combined higher cpu/nb clocks lower the overclock head room u will have, verses more heat

lower north bridge clocks, higher the cpu clock u will achieve, reverse vesa

 

[Enmity]

alright so i ran vantage and my cpu score has dropped quite significantly from over 31k to about 27k since running the ram divider. Perhaps its a stability issue with having the nb so high...needs more tweaking.

thanks jr, im aware of the advanced bios features however im yet to figure out exactly how useful the unlocked settings are with my board - it basically unlocks a few more memory settings and HTlink stuff - haven't sussed that out yet.

I was pretty sure that with amd they generally like low cas as versus high mhz, thanks erocker for backing up that theory

actually i just thought of another question - how effective is overclocking the HTlink? i know it can help with memory bandwidth but does it really show?...and also i've heard some stories of leaving the htlink around 1.8 - 2.0 and it'll "sometimes" allow for higher cpu clock. My chip is only stable slightly over 3.8 - i think 3840Mhz is about tops so far.

 

[erocker]

4-4-4-12 or 1000Mhz @ 5-5-5-15 will give u same speeds, according that the rest of other timing are tight, your nb clock is way to high, higher nb clocks, will result in a lower overall cpu clock

hears some examples
cpu 3800mhz 1.5v nb 2400mhz 1.25v
cpu 3800mhz 1.6v, nb 2880 1.4v

its a balance thing, if combined higher cpu/nb clocks lower the overclock head room u will have, verses more heat

lower north bridge clocks, higher the cpu clock u will achieve, reverse vesa

Yes and no, it depends on the CPU and the motherboard. If he is able to get 3.8ghz and a 2880mhz NB that is great. Most PII's aren't able to be 24/7 at anything over 3.8ghz anyways. More heat comes from raising the NB/CPU VTT voltage.

24/7 for me is 3.8ghz 2800mhz NB. CPU volts= 1.475, NB/CPU VTT = 1.3v, NB = 1.24v. My system runs quite cool with these settings. If I want to do 4ghz it takes 1.525v for the CPU, and a 2400Mhz NB. (With my PII x4 955)

 

[Corduroy_Jr]

i own a am2+ gigabyte board, and a phenom II 940, and yes your board has that option to choose nb voltage, ht link does not give u no extra speed, leave at 2.0ghz

 

[Corduroy_Jr]

Yes and no, it depends on the CPU and the motherboard. If he is able to get 3.8ghz and a 2880mhz NB that is great. Most PII's aren't able to be 24/7 at anything over 3.8ghz anyways. More heat comes from raising the NB/CPU VTT voltage.

24/7 for me is 3.8ghz 2800mhz NB. CPU volts= 1.475, NB/CPU VTT = 1.3v, NB = 1.24v. My system runs quite cool with these settings. If I want to do 4ghz it takes 1.525v for the CPU, and a 2400Mhz NB.

i agree that's some nice clocks he got, but u have to agree lowering nb clocks will result in a higher cpu clock, with lower vcore voltage with less heat

 

[Enmity]

4-4-4-12 or 1000Mhz @ 5-5-5-15 will give u same speeds, according that the rest of other timing are tight, your nb clock is way to high, higher nb clocks, will result in a lower overall cpu clock

hears some examples
cpu 3800mhz 1.5v nb 2400mhz 1.25v
cpu 3800mhz 1.6v, nb 2880 1.4v

its a balance thing, if combined higher cpu/nb clocks lower the overclock head room u will have, verses more heat

lower north bridge clocks, higher the cpu clock u will achieve, reverse vesa

thats really useful thanks mate, it makes sense really. I guess ive gotta find the right balance for my hardware. here's a screen of where im at right now..

I've gotta gap it to work now, I appreciate any help or suggestions cheers guys.

 

[erocker]

Your NB/VID voltage looks awfully high. Set it back to 1.3v - 1.32v

 

[Enmity]

i'll do that now before i go, thanks man

 

[erocker]

i'll do that now before i go, thanks man

If you look at your temps now, then after you lower the NB/CPU VTT voltage there should be a good temp drop.

 

[Corduroy_Jr]

hes lucky to achieve those clocks with such a low voltage, compared to my dud of pII 940, highest i got was 3700mhz 1.6250v, nb 1.45v 2800mhz

 

[Corduroy_Jr]

could be that my Asus M4A79-deluxe board is a bad overclocker or just pure bad luck getting a bad batch of a cpu, ethier way looking to get a Asus Crosshair III Formula, praying ill get a higher clock

 

[Enmity]

as soon as i dropped that nb volt down to 1.31 the system crashed lol...im at work now so cant test for the moment but i'll try and find the lowest stable voltage for nb later.

also, i never thought to check whether after unlocking extra settings in bios (ctrl + f1) to check if the nb would have +volts

 

[cadaveca]

could be that my Asus M4A79-deluxe board is a bad overclocker or just pure bad luck getting a bad batch of a cpu, ethier way looking to get a Asus Crosshair III Formula, praying ill get a higher clock

Crosshair3 rocks...300x12.5(3750mhz), 2700NB, 2400HTT(running crossfire), 1600 mem, with a crappy 720BE @ 1.55v. NB @ 1.3625v. all other volts @ stock.

Enmity..max v for NB(offically from AMD) 1.425v, cpu 1.55v. Just keep it under 57c or so. the lower you get the temps, the better it will clock.

 

[Enmity]

ah i see, i'll try 1.35 when i get home, then 1.375 temps are pretty good, doesn't really go much over 52C from what i've seen.

 

[Corduroy_Jr]

ah i see, i'll try 1.35 when i get home, then 1.375 temps are pretty good, doesn't really go much over 52C from what i've seen.

good job Enmity aim for no higher then 55c what speed is your nb at?

 

[Enmity]

nb is at 2868 as in screenie still gotta find out why my cpu score in vantage dropped so much at these settings though.